<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .container {
        width: 300px;
        height: 200px;
        margin: 0 auto;
        text-align: center;
        display: flex;
        flex-direction: column;
        justify-content: center;
      }
      .num {
        font-size: 42px;
        margin-top: 20px;
      }
    </style>
  </head>
  <body>
    <div class="container">
      <div>
        <button id="startTimerBtn">开始计时</button>
        <button id="stopTimerBtn">停止计时</button>
      </div>
      <div id="num1" class="num">0</div>
    </div>
    <div class="container">
        <div>
          <button id="startTimeoutBtn">开始计时</button>
          <button id="stopTimeoutBtn">停止计时</button>
        </div>
        <div id="num2" class="num">0</div>
      </div>
    <script src="./js/index.js" type="module"></script>
  </body>
</html>

